1. Field of the Invention
The present invention relates to a vehicle lighting fixture such as a headlamp, and more specifically to a construction of a venting hole provided in a housing of a vehicle lighting fixture.
2. Description of the Prior Art
FIG. 3 shows an example of a conventional venting hole of this kind. In order to provide a permeability within a chamber formed by a housing 11 and a lens 12 of a headlamp 10, a pipe-like venting hole 91 is projected externally of the housing 11. A rubber pipe 92 or the like is connected to the venting hole 91 to prevent entry of water drop.
The headlamp 10 encases therein a structure for example such as a reflecting mirror 13 which constitutes part of the headlamp 10.
However, in the aforementioned conventional venting hole 91, the rubber pipe 92 is connected thereto to thereby surely prevent entry of water drop but dust floating in air is sucked thereinto. With the passage of time in use of the headlamp 10, dust is accumulated on the reflecting mirror 13 and the like. As a result, there gives rise to a problem of insufficient illuminance. This problem should be solved.